Calculate the percent activity of the radioactive isotope strontium-89 remaining after 5 half-lives.

1 answer:

5 0

The answer to this question would be: 3.125%

Half-life is the time needed for a radioactive molecule to decay half of its mass. In this case, the strontium-89 is already gone past 5 half lives. Then, the percentage of the mass left after 5 half-lives should be:
100%*(1/2^5)= 100%/32=3..125%

You might be interested in

5. Didderent betwen group and period.

Ronch [10]

A group goes vertically and a period goes horizontally.

(a group goes down and a period goes across)

3 0

2 years ago

Hemoglobin in your blood does not use elemental iron. It uses iron in the form of Fe2+(aq).

valina [46]

Explanation:

Balanced chemical reaction equation will be as follows.

$2Fe^{2+}(aq) + 2H^{+}(aq) \rightleftharpoons 2Fe^{3+}(aq) + H_{2}(g)$

In human body, the neutral iron changes into $Fe^{2+}$ (aq) cation. There will be an oxidation-half reaction and a reduction-half reaction. Equations for this reaction are as follows.

Oxidation: 2Fe^{2+}(aq) \rightleftharpoons 2Fe^{3+}(aq) + 2e^{-}[/tex] .... (1)

Reduction: $2H^{+}(aq) + 2e^{-} \rightleftharpoons H_{2}(g)$ ...... (2)

On adding both equation (1) and (2), the overall reaction equation will be as follows.

$2Fe^{2+}(aq) + 2H^{+}(aq) \rightleftharpoons 2Fe^{3+}(aq) + H_{2}(g)$

Therefore, neutral iron is a part of Heme - b group of Hemoglobin and in an aqueous solution it dissolutes as a part of Heme group. Hence, then it becomes an $Fe^{2+}$ cation.

3 0

2 years ago

An organism's _______ describes its genetic composition. An organism's _______ describes its appearance or observable characteri

harina [27]

I think it is C species and heredity

5 0

3 years ago

I need help please.

murzikaleks [220]

Answer:

Explanation:

4 0

2 years ago

What is the Definition of "Folded Mountain" in science terms?

just olya [345]

Fold mountains are mountains that form mainly by the effects of folding on layers within the upper part of the Earth's crust. Before either plate tectonic theory developed, or the internal architecture of thrust belts became well understood, the term was used for mostmountain belts, such as the Himalayas.

3 0

3 years ago